Updated September 25, 2026. Fact-checked against veterinary sources; review by a licensed veterinarian is in progress. See our editorial policy.
Quick answer: Prescription, or therapeutic, diets are formulated to help manage specific medical conditions, such as kidney disease, bladder stones, digestive disorders, food allergies, and obesity. Several major manufacturers make comparable diets in each category, so if your pet won’t eat one brand, your vet can often suggest another. They work best when fed exactly as directed, without extra foods mixed in.
Main categories
- Kidney (renal): restricted phosphorus, moderate protein. See kidney diets for cats
- Urinary: dissolve or prevent certain stones and crystals
- Gastrointestinal: highly digestible, low-fat, or high-fiber options
- Hydrolyzed and novel protein: for food allergy trials and chronic gut disease
- Weight management: fewer calories with added fiber and protein
- Diabetes, liver, joint, cognitive, and dental formulas
How brands compare
- Major brands make similar diets for most conditions, with differences in exact nutrient levels, texture, and taste
- Your vet will match the diet’s nutrient profile to your pet’s needs
- Wet and dry versions differ in water content, which matters for urinary and kidney health
Tips for success
- Transition gradually
- Don’t mix in other foods unless your vet says it’s OK
- Ask about approved treats
- Keep follow-up appointments
- Tell your vet if your pet refuses the food. Alternatives exist
Sources
- WSAVA Global Nutrition Committee: Nutrition toolkit
- AAHA Nutrition and Weight Management Guidelines for Dogs and Cats. 2021
- Lulich JP, et al. ACVIM small animal consensus recommendations on the treatment and prevention of uroliths in dogs and cats. J Vet Intern Med. 2016
This article is for general education and is not a substitute for care from your own veterinarian. Learn about The Pet Vet and our editorial policy.